Oh, Lady, Lady (1920)

Having long ago left his country sweetheart, May Barber, Willoughby Finch is about to marry Molly Farringdon when a simple phone message from May leads him to the mistaken belief that she plans to disrupt the wedding. May, now an actress known by her stage name of Rilla Rooke, meets and falls in love with Finch's best man, Hale Underwood, on the train taking her home from a successful tour. Learning from a friend that Finch is in distress over a vamp's threat to ruin his wedding, May offers to pose as Finch's lover to drive the vamp away. Her appearance at Finch's wedding rehearsal, however, only confirms Finch's worst suspicions, since May and the vamp that he fears are the same. May's charade also alienates Underwood, but she clarifies the situation that evening at a jazz party at Underwood's apartment, and both pairs of lovers are reunited.